Facile synthesis of amorphous carbon-coated bismuth phosphate nanocomposite for lithium-ion battery anode with ultra-long cycle stability

Abstract

Herein, we report a novel BiPO4@Ketjen Black nanocomposite as long cycle life lithium-ion battery anode. The BiPO4@Ketjen Black nanocomposite is obtained via a simple and mild molten salt preparation followed by post-milling. When assembled with metal lithium sheets for half battery, BiPO4@Ketjen Black nanocomposite delivers a high capacity and rate performance as 317 ​mAh g−1 with current density of 100 ​mA ​g−1 after 100 discharge-charge cycles and 210 ​mAh g−1 delithiation capacity at 200 ​mA ​g−1 after 1500 cycles. A superior result as 100 ​mAh g−1 delithiation capacity at 1 ​A g−1 after 5000 cycles is acquired with a very low capacity attenuation rate of 0.013% per cycle. The enhanced electrochemical performance of BiPO4@Ketjen Black nanocomposite can be attributed to the formation of Bi nanoparticles uniformly dispersed in Li3PO4 inert matrix and amorphous carbon during the lithium impregnation process in the first cycle. This work revealed that the as-prepared BiPO4@Ketjen Black anode has great potential for development in lithium ion batteries.